1. Technical Field
The invention relates to a semiconductor device and a method of operating the same. More specifically, the invention relates to a read operation of a semiconductor device.
2. Related Art
A single-level cell (SLC) in which one-bit data is stored in one memory cell has been used for a semiconductor device, but due to a large capacity of the semiconductor device, a multi-level cell (MLC) in which a plurality of bits of data are stored in one memory cell is being developed. Recently, a type of the multi-level cell is subdivided, a cell in which two-bit data is stored in one cell is referred to as a multi-level cell, a cell in which three-bit data is stored in one cell is referred to as a triple-level cell (TLC), and a cell in which four-bit data is stored in one cell is referred to as a quadruple-level cell (QLC).
As such, as the number of bits stored in one cell is increased, program and read operations are performed unlike those of the single-level cell. For example, the program operation on the most significant bit (MSB) (an MSB program operation) is performed after the program operation on the least significant bit (LSB) (an LSB program operation) is performed. The read operation is performed according to each program state after it is determined whether a selected page is a page on which the LSB program operation is performed or a page on which the MSB program operation is performed.